wardite

Wardite is a rare phosphate mineral with the chemical formula NaCa$_{3}$Al$_{8}$(PO$_{4}$)$_{7}$(OH)$_{9}$·13H$_{2}$O. It is a hydrous sodium calcium aluminum phosphate hydroxide. Wardite typically occurs as small, translucent to opaque, white to pale green crystals, often forming drusy coatings or radiating aggregates. Its crystal system is monoclinic. The mineral was first described in 1890 and named in honor of Henry Augustus Ward, a mineral collector and founder of the Ward's Natural Science Establishment in Rochester, New York. Notable occurrences of wardite are found in the United States, particularly in the phosphate deposits of Arkansas, and also in other locations worldwide. It is often found associated with other phosphate minerals, such as wavellite and crandallite. Wardite is not a commercially significant mineral, but it is of interest to mineral collectors and geologists due to its rarity and distinct mineralogical properties. Its hardness is between 4.5 and 5 on the Mohs scale, and it has a specific gravity of approximately 2.15.